TAPE GUIDE (Mar. 1992)

Playing Type IV Tape

Q. I've read that metal-particle tape (Type IV) may be played on any deck.

It was my understanding that metal tape should be played only on decks with the appropriate switching control.

I was led to believe that this is due to the metal formulation being different from other formulations (Types I and II). If metal tape is played on decks without such switching, would there be damage to the heads or other parts of the cassette deck? Also, is there any difference in the head composition of decks with and without the switching control for playing metal tape or the other types?

-E. T. Shields, Barboursville, N.Y.

A. Yes, metal-particle tape may be played on any deck. No harm will come to the heads or other components of the deck.

Cassette decks generally provide two kinds of playback equalization: 70 uS for Type II and Type IV and 120 uS for Type I. Type IV tapes require the same, 70-uS playback equalization as Type II tapes; if Type I (120-uS) equalization is used, the only result will be a bit of emphasis in the treble range, easily corrected by tone controls. So metal tapes can be played even on inexpensive equipment that has only the "normal" 120-uS equalization.

For recording, however, Type IV tapes require much higher bias than Type I or Type II cassettes. Recording with insufficient bias will result in high distortion and excessive treble. Some inexpensive decks and recorders can not provide proper Type IV bias, and they may also be unable to adequately erase material previously recorded on metal tape.

Metal tape calls for suitable record heads in order to accommodate the greater bias current and greater signal current required by this formulation. In fact, in the early days of metal tape, one of the chief problems was to devise suitable heads for it.

Sticky Problem

Q. I'd appreciate your throwing light on a problem I've encountered with four or five commercially recorded cassettes during the last year. On each occasion my tape deck stopped during play. On removing the cassette and taking up the slack, I found that the tape was somewhat harder than normal to wind manually. Presumably this accounts for the stopping, but I'm puzzled about the cause of the resistance to tape motion. Usually the fast forward and rewind modes still work, although during the course of this I have sometimes heard unusual noises, notably an intermittent squeaking/sizzling noise. On three of the tapes involved, the problem has not recurred.

-Evan K. Jobe, Lubbock, Tex.

A. Possibly owing to excessively low humidity, the tape may have picked up static charges that caused the tape layers to attract each other and therefore stick. Static charges could also account for the "sizzling" noise. Of course, this is just a guess.

The tapes employed for prerecorded cassettes in general are not famous for being of top quality, and therefore might possess characteristics which led them to perform as they did. Components of the cassette might be responsible; for example, faulty slip sheets might interfere with easy tape travel.

If a tape still gives you the same problem, try giving it a vigorous slap across something not too hard, such as a book or your hand. And hope for the best.

Fidelity of CD Dubbings

Q. After carefully setting bias (manually) on my cassette deck, which has Dolby HX Pro, and using Dolby C noise reduction, I can still detect a slight difference between the dubbing and the CD. Is it unreasonable to expect the two to sound identical to 50-year-old ears?

-Gerald Pasternack; Colts Neck, N.J.

A. In terms of signal-to-noise ratio, distortion, and wow and flutter, CD performance is considerably better than that of a cassette deck. Also, frequency response of a CD is flatter and more extended. On the other hand, the measured differences tend to be greater than the audible differences. On the whole, given a good deck and good tape and proper recording procedure, sound quality of a cassette deck should be quite close to that of CD.

Identical or nearly identical performance is promised by the DAT deck, which is at last on the market. On the other hand, the cassette format has taken an important step upward with the introduction of Dolby S noise reduction. This development not only improves S/N but is licensed only to deck manufacturers whose decks conform to high standards set by Dolby Laboratories. In 1992, we should see both the Digital Compact Cassette and the Mini Disc, which are claimed to closely approach (but not quite equal) Compact Disc performance. And finally, we have recordable CD, which has so far come down from about $150,000 to $7,000 or so but will probably become even more affordable in the future.

Remote-Control Compatibility

Q. I have a problem concerning re mote control of my system. My receiver is a Kenwood, and my deck is a Pioneer. The problem is controlling my deck with the remote control of the receiver. I have written both companies asking about this, and both stated this should work, but it doesn't. I hope you can provide me with some advice, short of buying components of the same make. I am thinking of buying a universal remote control. Do you think this would work?

-Tony Sanders; APO San Francisco, Cal.

A. Your question implies that the receiver's remote control is of the learning type, so that it can also control a cassette deck, VCR, etc. While a learning remote can ordinarily learn to control other components made by the same manufacturer, it may or may not be able to do so for components from other manufacturers. I gather that you have tried and failed.

Yes, a universal remote may solve your "problem." You should buy this item on condition that it can be re turned within a stated time with no questions asked. I put the word problem in quotes, because I don't see it as anything but a minor inconvenience.

Separate remotes, while occupying more space, are more quickly identifiable as to what goes with what, and they avoid a rather intimidating array of buttons, some of which do double duty and therefore tend to be confusing.

(Source: Audio magazine, Mar. 1992, HERMAN BURSTEIN)

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